This invention is in the field of ignition systems for fuel burning engines and in particular in such ignition sytems which have both a capacitor and an inductive winding of an ignition transformer cyclically charged and discharged in discharge aiding mode, and more particularly wherein such system produces a high velocity igniter arc.
Accordingly, neither the Kettering, capacitive discharge, nor AC system is capable of delivery of sufficient quantities of energy to fire an igniter, in order to enable the igniter to cause all fuel in an engine cylinder to be consumed and not wasted by failure of the ignition arc to burn same.
A further disadvantage of prior art ignition systems is that they cannot charge the inductor or transformer winding and the capacitor in a way so that discharge currents therefrom are additive and aid each other.
A still further disadvantage of the prior art systems is their inability to deliver sufficient energy to fire an igniter for extended periods of time.
Yet a further disadvantage of the prior art systems is their inability to deliver more than one ringing cycle during an igniter firing period.
Yet another disadvantage of the precharged inductor or capacitor prior art systems is their inability to rapidly charge the inductor due to use of DC power, with attendant inability to deliver sufficient energy to fire an igniter so as to effectively cause all the fuel to burn during an igniter firing period.
Yet another important disadvantage of any prior art system is the inability of the system to accelerate the arc luminous particles to such high velocity so that such arc can adequately overcome internal engine and fuel-flow pressures. Such prior art systems are therefore unable to use an igniter that develops long arc lengths between its electrodes. Such deficiency results in initiation of a small fuel ignited nodule during the initial ignition period which is insufficient in mass and area to cause all fuel in a cylinder to be consumed and not wasted.
Other disadvantages with such prior art systems reside in their complexity due to the need of a large quantity of electronic components which also gives rise to unreliability as well as high cost of production.
Exemplary of prior art systems is U.S. Pat. No. 3,714,507 which is a capacitive discharge system. A charge retention storage capacitor is charged by a relatively high DC voltage source, and the charge from the charge capacitor is discharged through an ignition transformer primary winding by utilizing a silicon controlled rectifier switch. Another capacitor across the primary winding is selected of such value so as to suppress electromagnetic interference due to discharge of the storage capacitor.
Another example of prior art is U.S. Pat. No. 3,312,860 which operates on a similar principle to that of U.S. Pat. No. 3,714,507, except that its high voltage DC power source is of a different design.
Still another example of the prior art is U.S. Pat. No. 3,972,315 which utilizes two ignition transformer primary windings. One of such windings is energized by the discharge of a precharged capacitor from a DC source; whereas the other of these primary windings has a a discharge current passing therethrough to combine with the capacitive discharge into the first named primary winding. This would be the principle of operation if the system were operative, but such system is precluded from operation by a hard-wire short circuit across the second named primary winding.
All of these exemplary systems miss the major point of technology of not utilizing rectangular or other AC power to feed the ignition transformer primary winding, and to feed such components as are connected in the primary winding circuit with AC power, and thus such systems cannot obtain the extremely high energy levels that would otherwise be possible when exciting the ignition transformer primary circuit components with AC power.
The technology applied by the prior art is also insufficiently advanced as to the mode of operation of an engine to obtain optimum performance and efficiency. Lack of knowledge prevails as to utilization of extremely long ignition arcs initiated at very advanced timing angles. Other relationships also unknown by the prior art is the relationship between the optimum timing arc ignition initiation angle and the engine rotational velocity.